10. If you ignore that niggle, you will regret it

11. Anti-blister socks are the greatest invention ever

12. Well, maybe the second worst, after sports-bra chafing

Which is the worst pain known to woman. Seriously, can someone please invent some sort of jiggle-stopping device for big boobs that doesn't cause friction burns after three miles?

13. Random strangers love to shout comments at you

If we had a penny for every time we'd heard an unwanted opinion ("Knees up, love!"; "What's the rush?"), we'd have at least enough cash for noise-cancelling headphones.

14. You're totally OCD

You mapped the route and psyched yourself up for a full 10K – only to arrive back at your front door more than half a km short. Gah! Cue: running up and down your street until you can stop dead on the dot of 10K.

15. If it's not logged, it didn't happen

There's no panic like getting back from a long run to realise you forgot to turn on Strava/MapMyRun/Nike Run. But how will I find out my splits?!?

16. Crossing that finish line is the Best. Feeling. Ever.

It doesn't matter if it's your first 5K or your gazillionth marathon, making it over that line results in a sudden rush of joy, pride, and er, bursting into tears (just me?).

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